Revised

Abstract

This paper details the design of rear upright for a JCU Tec-NQ (JTR) Racing Motorsport, Formula Society of Automotive Engineers (FSAE) race car using Aluminium Alloy 7075-T6 through the use of a track simulator developed by RMIT Racing, forces on the upright were calculated and an upright was designed in SolidWorks. To ensure optimal design with the aid of Finite Element Analysis using ANSYS workbench, three main load cases with combination of drive cases (acceleration, braking, and left and right turn) were used to evaluate performance of the rear upright. They include fatigue of upright, single bump loads and the zero-based fatigue loading of the calliper-mounting bracket. For the fatigue loading of the whole upright, it was observed that the greatest stress throughout the four drive cases occurred in a left hand turn. For single bump loads, the upright could withstand a vertical bump load of stress value significantly lower than the ultimate tensile strength. For the fatigue analysis on the brake calliper mount, the resulting safety factor plot presented a minimum factor of three for infinite life. Other relevant analysis were presented, such as sphere of influence and exaggerated deformation which showed that the upright will experience a maximum deformation of 0.132mm during the worst case lap scenario (left hand turn). The material considered for the design of the rear upright was Aluminium Alloy 7075-T6 as it has superior mechanical properties in terms of stiffness, fatigue and tensile strength for the application compared to both the Alumec alloy and Aluminium Alloy 6061-T6 considered in this paper.